gossylic lactone

5,5'-Diisopropyl-7,7'-dimethyl-3,3',4,4'-tetrahydroxy-8,8'-bi[2H-naphtho[1,8-bc]furan]-2,2'-dione

3,3',4,4'-Tetrahydroxy-5,5'-diisopropyl-7,7'-dimethyl-8,8'-bi[2H-naphtho[1,8-bc]furan]-2,2'-dione